From March 2, 1955, through March 6, 1958, 3,421 wild mammals were captured in southwestern Georgia. Of 3,002 animals considered to be adequately cultured, 291 (9.69%) were positive for leptospires. Of 25 species examined, isolates were obtained from 10, as follows: house mouse, cotton rat, cottontail rabbit, opossum, raccoon, striped skunk, spotted skunk, gray fox, wildcat, and feral pig. One to seven serogroups were found in single feral mammal species. None of the animals displayed physical symptoms of illness or exhibited gross pathology.
The ballum serogroup was identified from isolates most frequently (49.2%) and was found in all host species except the feral pig. The pomona serogroup comprised 15.8% of the total number of isolates identified and occurred in three host species. The hyos serogroup was found just as frequently and occurred in four host species. The australis A, autumnalis, hebdomadis, and grippotyphosa serogroups comprised 19.1% of the total number of isolates identified. Data obtained suggest that the opossum, raccoon, and striped skunk are the current primary large wild mammal hosts of leptospires in southwestern Georgia.
A report of newly established host species includes: the spotted skunk and cottontail rabbit for ballum; the striped skunk for members of the hebdomadis and hyos serogroups; wildcats for members of the hyos serogroup; and the opossum for members of the australis A, autumnalis, and hebdomadis serogroups.
Urine specimens from 372 mammals were examined microscopically for comparison with culture results from tissues. Only 2 of 55 urine specimens from culturally positive hosts were found positive by microscopic procedures. In 15 instances in which microscopic examinations were reported “doubtful,” 5 of the tissues demonstrated leptospires. Negative results were reported from 48 of the urine specimens found positive through kidney culture procedures.